1. Field of Invention
This invention relates to a time striking device for a timepiece, and more particularly to a time striking device for a timepiece performing time striking action in an analog type timepiece with high accuracy.
2. Description of Prior Art
A time striking device for a timepiece is well-known in the art as a means for time striking or chiming at indicated times at such right-hour that a minute hand points out 0 minutes and at such half-hour that the minute hand points out 30 minutes, and it is of wide use in various clocks since the time is known without watching the time indicating hands.
In an analog type timepiece in the recent years, an electric time striking means is used in the time striking device with electronization of timepiece device. Ordinarily, this electric time striking means is driven by an electromotor to perform mechanical time striking or chiming. The operation of the above mentioned time striking means is controlled by an electric contact means, and, in order to switch it on and off, the electric time striking means has a time striking selecting cam plate in its means which rotates synchronously with a time indicating gear train of the timepiece to operate the electric contact means at the striking time. In other words, the time striking selecting cam plate is linked to a minute wheel rotated once an hour, and operates the electric time striking means at the striking time.
As mentioned in the above, the striking time is controlled by the time striking selecting cam plate which rotates in comparatively slow speed, and the prior time striking device has such drawbacks that an accurate time striking action cannot be obtained since it produces such a late striking phenomenon as the time striking action is performed after a time indicating hand passes the striking time. In particular, in the accurate analog type timepiece in the recent years using a crystal oscillator, the time striking accuracy has been strongly requested to be improved. Furthermore, it is preferable that the striking time be accurately coincided with a second indicating hand. Accordingly, the second indicating hand and the striking time are required to be correctly set each other.